Clamp for stringing rackets



P 1952 E. H. SERRANO 2,608,737

CLAMP FOR STRINGING RACKETS Filed Nov. 17, 1949 V T 40 6 IN EN OR BySerrana azq Patented Sept. 2, 1952 ;This invention relates certain newand useful Patents Nos. 2 ,188,250,dated January23, 1940,

on 2,154,870, dated April 18-, 1939, and more espe-' oi'ally .in thestring tensioning device and string clamping or gripping :means 1 ofvthe string i holding: arm thereof so'as to-prevent breaking of thestring-when tension is placed thereonduring the stringing of the racket.1 1 1 It is also an object of the invention .to provide a. novel stringholding arm having .normally'expandeduorseparate'd jaws with headsdesigned to'receive and grip. the string therebetween" or permitwwrapping or winding of the string thereon: and gripping thereofbetwee'nv the jaws when forced together so that the string does not takeany abrupt anglesor bends and may withoutinjury thereto be safely placedunder the desired tension during the stringing operation in proper linewith the holes of the racket string frame so that breaking or partingof'thestring is guarded against, ltogether with a manually-actuated camlever"'means for forcingjthejaws of-the puller ar'm'int'o stringgripping or clamping relation or for releasing the same fohmoV'ement'automatically to. normally expan'ded'or separated position for furtherthreading of the string-through the heads or drum in order toflrmlyclamp and hold or anchor the stringthereto when under tensionduring the stringing of the "racket, and the requirement of frequentreplacement of such rubher band in order to effectively clampor anchorthe string'to the holding arm. 5

A still-further and important object is to pro vide simpleand novel cammeans for forcing the sections or jaws of the movable split holding armtogether or forreleasing the camming action wherebythe' jaws-willseparate to release'the grip old-the string,saidmeans including aforked ,U-NI-IEDq-STATES PATENr-oFFicE QoLAm ron KSTRINGINGRACKETSY-ZH e-LPF W t 1:3 Applieati onNovember 1'7, 1949, Serial No. 127,804 7Claims. (01. 24-250 I 1 leverjstraddlingvthe normally expanded sectionsof the holding arm and a connection through the arm between the arms ofthe lever having coacting cam. surfaces washers. for efiecting thegripping and releasing action of the jaws of the holding arm'; a

. With the above and other objects in 'view that willzbecome apparent asthe nature of theinvention'is'better understood,.the same consists inthe novel form, combination and arrangement of parts hereinafter morefully described, shown in the accompanying drawings, and claimed.

Inthe drawing: I. 7 Figure 1 'is a. fragmentary perspective view showinga'portio'n of the-racket frame and the improved holding arm of theracket stringing apparatus of my ,prior patent with a section of thegutstring extending therebetween gripped or clamped and held undertension;

v Figure 2 is an enlargedfragm'entary inside elevation ofthestring'holding armwith the jaws 30 holes of the racket string irame'forcompletion in released position 7 Figure-3 'is' a: view similar toFigure 2 with the jaws in'clamping position; I

Figure 4 is an enlarged fragmentary vertical sectional view taken online 4-4 'of Figur 1; 4

' Figure 5'is' a fragmentaryipcrspective detail view of one end of thesquared belt or shaft of the jaw actuating cam means of the holdinga-rm;

Figure 6'is a fraginentary detailof an'attaching end of the forked-camactuating lever ofthe holding arm jaws,arid 7 Figure? is a detail faceview of one "of the camming washers. 4 3

Referring-more-in detail to the accompanying drawing, the racketstringing apparatu to which the present improvement is applied, is ofthe type shown in my prior Patents Nos. 2,188,250, dated January23,"1'94'0, or 2,154,870, dated April 18, 1939, hereinb'efore referredto, in which the string frame l0'of the racket is'held 'in clampsor jawsat the throat and nose portionsof the apparatusv in' the mannershown'i'n the patfint with the string ll eXtendingfthrough the staggeredor otherwise arranged holesl l2 through the frame. The bar or rod [3 ofthe rectangular cross-section as shown, correspondstothe laterallyoifset end slot the rod 29 of 'saidPatent 2,188,250, which slidably'moves inthe anti-iriction bearings of the housings '28 atdiametrically.opposite sides of the upper end of thetubular post I0 .tocause movementof the'arm 32 o f the patent carrying the string 'grippingdruml forplacin the string under t ension'. V 4. R H However, in thepresent'embodiment, the string holding arm is designated generally at14, the

by swinging the lever or handle downwardly to permit the separation ofthe jaws under the action of the spring 27 as previously explained. Theracket stringing apparatus is of course of the type wherein a stringtensioning device is adapted to have a string coiled therearound andheld or clamped by the gripping jaws to exert a holdin force on a stringthreaded through a tennis, squash or badminton frame and to beinefiective during continued movement after the string has received thedesired tension, and wherein a tensioned portion of the string is heldunder tension while the tensioning device is being engaged with anotherportion of the string and wherein means is provided for holding thetension against movement, and, also, wherein a racket supporting head ismounted upon the upper end of a standard and wherein the string istensioned by sections with a tensioned string section held under tensionwhile tensioning another section, whereby with proper adjustment of thestring tensioning means any racket frame may be properly and efficientlystrung.

While there is herein shown and described the preferred embodiment ofthe invention, it is,

nevertheless to be understood that minor changes may be made thereinwithout departing from the spirit and scope of the invention as claimed.

I claim:

1. In a string holding means for a racket stringing apparatus, stringtensioning means including a string holding arm supported for tensioningand releasing movements, said arm including a rigid section and apivoted section movable toward and away from the rigid section, enlargedoutwardly projecting semi-ovate jaw heads on the upper ends of thesections having horizontally grooved outer peripheries and fiatsubstantially parallel inner faces, the inner corners of the heads beingconvexly rounded and the outer corners in alignment for winding a stringthereon 2. In a string holding means for a racket stringing apparatus,string tensioning means including a string holding arm supported fortensioning and releasing movements, said arm including a rigid sectionand a pivoted section movable toward and away from the rigid section,enlarged equal sized outwardly projecting semi-ovate jaw heads on theupper ends of the sections having horizontally grooved outer peripheriesand fiat substantially parallel inner faces, the inner corners of theheads being convexly rounded and the outer corners in alignment forwinding a string thereon and between said faces, a shaft extendingthrough the sections for rotation, said sections having diametricallyconcaved outer camming recesses at their outer sides, diametricallyconcavo-convex cam washers having their convex faces fitting saidrecesses, a polygonal bolt and between said faces, a shaft extendingthrough extending through aligned circular bores through the sectionscentrally of the camming recesses with the washers fixed thereonoutwardly of the recesses to turn therewith and slide thereon, a forkedlever having ends fixed on the bolt to turn therewith outwardly of andagainst the washers to force the jaw heads and sections in contractedrelation in one position of the lever to grip the string and release thesame for expansion and separation in another position, and a springbetween the sections to normally separate the same and jaw heads.

EDMUNDO H. SERRANO.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Great Britain May 18, 1933

